/Engine/Source/Editor/Kismet/Public/BlueprintEditorModule.h
Register a customization for for Blueprint variables
virtual [FDelegateHandle](API\Runtime\Core\Delegates\FDelegateHandle) RegisterVariableCustomization ( [FFieldClass](API\Runtime\CoreUObject\UObject\FFieldClass) * InFieldClass, FOnGetVariableCustomizationInstance InOnGetVariableCustomization )